A difference in perception between sight and balance (the inner ear) occurs when an individual is placed in a moving environment without visually perceiving this movement, and vice-versa. In such a situation, the eye perceives a stable environment inside of a moving object, for example, inside a cabin of a ship that is moving, whereas the inner ear perceives the opposite information. It feels the ship's movement. This contradiction or difference in perception is the cause of motion sickness (sea sickness, air sickness, car sickness, etc.), also called kinetosis. In essence, the information perceived by the inner ear and the information that the individual sees are in contradiction.
More particularly, an enclosure can define a reference, e.g., a two-dimensional line or a three-dimensional plane, that is normally parallel to the terrestrial horizon. Hereinafter, the reference is referred to as the enclosure's “horizontal reference.” When the enclosure undergoes a rolling movement, the horizontal reference forms an angle with the terrestrial horizon, and this angle corresponds to the roll angle of the enclosure. A viewer who moves with the enclosure would then expect, based on movement of fluid in the inner ear, the horizon's angle to correspondingly change. However, when the environment of the enclosure dominates the viewer's field of vision and the expected movement of the horizon is minimally or not-at-all perceived, motion sickness can occur.
Examples of anti-kinetosis devices for addressing this situation are known in the prior art. For example, U.S. Pat. No. 6,783,237 B1 proposes, in order to act against kinetosis, glasses that contain a visual balancing device that added on or integrated to any support (i.e., glasses) that must be positioned in the individual's peripheral field of vision. It is made of a tube or pipe or any other container closed on itself, impermeable, and transparent or translucent, in which at least two substances are contained which are in different states and/or masses (for example, one being in liquid form and the other in gaseous form (stained water and air)), such that the interfaces between these substances mark visible level reference points.
Preferably, the tube closed on itself assumes the general shape of a ring or of a torus inserted or integrated into a lens or a frame with or without a lens, or even affixed by gluing or clipping. At least one of the two substances that it contains is a liquid, such that it functions in a manner fundamentally comparable to that of the inner ear. Alternatively, the visual balancing device can be manifested in a virtual or luminous image of the same type, projected or integrated into a lens of glasses, obtained by means of an electronic device consisting of, for example, a sensor (gyroscope or any other source of information or sensor of the environmental or mobile position), to detect variations of the position relative to gravity. The information, possibly after handling by a computer, is then made available to the eye or eyes by an imaging or lighting system, for example, in the form of an inside or outside perimeter of a screen, or in the form of an animation in one or more screens, wall-mounted or not, or columns, or even in the form of a lighting system, for example, by light beams.
In such a device, perceptual problems could arise, for instance due to lighting level variations. Consequently, the device is less efficient depending the contrast or lighting.
DE10 2014 210170 A1 discloses a matrix-like arrangement of LED fields in the inner panel, on the rear side of the front seat and/or in the region of the floor of a motor vehicle. An artificial horizon can be generated, which can also be varied as a function of the driving situation. Certain LEDs are driven on the backs of the front seats in such a way that an artificial horizon is obtained for changes in direction of the motor vehicle. In the case of a straight-ahead drive, selected LEDs are controlled in such a way that an artificial horizon is obtained which is approximately horizontal.
The disclosed device is configured to act on the central or front visual field, while it has been shown that to reduce or prevent kinetosis, it is better to act on the peripheral visual field. The mobilization of the central or front visual field by the use of complex images or LED matrices obstructs the viewer's voluntary focus field and causes more fatigue. Moreover, such arrangement only works for people sitting in the rear seats.
US2004/217234 A1 discloses a system for presenting to aircraft passengers a series of images that simulate or represent the view external to the aircraft, in a manner that corresponds, at least in part, with the motion the passenger feels. A passenger bay includes a display having one or more portions that present to the passengers images that move in a manner that is at least partially coupled to the movement of the aircraft. The display can include a plurality of display portions, consisting of forward display portions positioned in the backs of the seats, side display portions positioned laterally adjacent the seats, and/or top display portions located above the seats. Such system shows too much visual information, with such information being poorly delivered and therefore hardly efficient.
Additional examples of devices for displaying images to simulate actual motion are found in WO 02/056792 A2 and WO 00/51673 A. All of these known devices are configured to act on the central or front visual field, whereas it is better to act on the peripheral visual field in order to reduce or prevent kinetosis. The mobilization of the central or front visual field by the use of complex images obstructs voluntary focus field and causes more fatigue.